Stochastic analysis of thermal cracking distress of asphalt pavements using the MEPDG thermal cracking model

The objective of the National Cooperative Highway Research Program (NCHRP) 9-22 project was to develop a Quality Assurance (QA) system for asphalt pavements in conjunction with Performance Related Specifications (PRS). The project was originally intended to use the Mechanistic-Empirical Pavement Design Guide (MEPDG) as the performance prediction simulator. However, since the probabilistic assessment of the MEPDG required hundreds, if not thousands, of solution simulations; the computational time was found to be excessive as a quicker solution was critically necessary. The study presented in this paper has been conducted as part of the effort associated with the development of a rapid thermal cracking (TC) prediction methodology and the estimation of the variance of TC. The Rosenblueth method and the Beta frequency distribution were used to estimate the first and second moments (average and standard deviation) of TC and its service life. The proposed TC stochastic framework showed a successful performance and was accordingly incorporated into the PRS QA system developed under NCHRP 9-22. The ultimate purpose of the developed QA system is to stochastically evaluate the incentive/disincentive for the contractors.